Erlotinib hydrochloride is marketed in the United States for the first time in 2004, and is applicable for local advanced or metastatic non-small cell lung cancer. The chemical name of erlotinib base (or referred to as erlotinib) is N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine, and the structural formula thereof is shown below:

U.S. Pat. No. 5,747,498 reported the synthetic method of erlotinib hydrochloride for the first time, Example 20 therein mentioned using flash silica gel column to separate and purify crude erlotinib base, followed by transforming it into its hydrochloride salt. The method of silica gel purification used in this patent is difficult to be applied in industrial production.
U.S. Pat. No. 6,900,221 reported obtaining the crystal form A or a mixture of crystal form A and B of erlotinib nib hydrochloride by direct reaction between 4-chloro-6,7-bis-(2-methoxyethoxy)-quinazoline and 3-aminophenylacetylene in the mixture of toluene and acetonitrile, and it is difficult to purify the product by methods of further recrystallization due to the very low solubility of erlotinib hydrochloride.
WO2008012105 mentioned the crystal Form I, Form II, Form III of erlotinib base, their pharmaceutical composition and their use in the treatment of cancer, wherein Form I and Form III are in form of hydrate and Form II is in form of non-hydrate. The Form I reported in this patent requires higher water content, so that a mixed crystalline of Form I and Form II is easily obtained during the preparation process, and Form II and Form III are obtained by air drying organic solvents containing erlotinib base at room temperature and ambient condition, so that they can not be applied in industrialized production.
WO2009024989 mainly described a novel hydrate crystal form of erlotinib base (water content: 1-10%), however, in viewing of XRD of this hydrate, what actually obtained is a mixed crystal of Form I and Form II, so that a crystal form with high purity can not be obtained.